A few months back, Doug and I discussed the 2006 San Francisco 49ers. While the team went 7-9, the 'Niners looked like fools gold. Consider this post from June, where Doug wrote:

[T]he 2006 San Francisco 49ers had the worst point differential of any 7-9 team in history....There has, in fact, only been one 6-10 team ever to post a worse point differential. And the 49ers compiled this differential against a weak schedule. San Fran was 31st out of 32 last year according to the simple rating system.

So they were either really lucky to be 7-9, or they were a clutch team that played their best football when it counted the most. You can probably guess which way I’d lean.

Here is one more interesting stat: the 49ers were outscored 113-251 in first halves of their games last year. Again, that’s a stat in which people will see what they want to see. But to my eye, it looks like the 49ers will need to improve greatly in 2007 just to finish with the same record. Fortunately for them, they do appear to have gotten better in the offseason, so it looks like that might happen.

The 49ers played a very weak schedule, yet still ranked 24th in points scored, 26th in yards gained, 28th in yards allowed and 32nd in points allowed. That's terrible, of course, but hidden by the 7-9 record. The 49ers average margin of victory was 7.4; their average margin of loss was 18.4. Basically, all that information is wrapped up in their pitiful Simple Rating System Rank of -8.7, second worst in the league (but best in the Bay area!).

Now you might wonder who cares what their simple rating system rank is, the team went 7-9. Here's my counter to that. I performed a regression analysis for each team since the merger using their SRS score as my input and their actual winning percentage as their output. It spit out a formula of:

Projected winning percentage = 0.500 + 0.28 * SRS score

So the 49ers projected winning percentage based on their SRS score was 0.256, while their actual winning percentage was 0.438. That difference of 0.182 led the league last year, and was the 27th biggest positive difference since the merger. Of the first 26 teams, 23 teams saw their winning percentage decrease the next year, one stayed the same, and two showed slight increases. Fourteen of the fifteen teams with the highest differential saw their winning percentage decrease the next season. The average change was a 0.183 reduction in winning percentage the following year.

Going the other way, of the 26 teams that "underachieved" the most -- that is, posted a strong SRS score but a relatively weak winning percentage -- 21 had a better winning percentage the following year, two stayed the same, and three saw small increases. None of the 16 most underachieving teams had a worse winning percentage the next year. The average change was a 0.213 increase in winning percentage in Year N+1.

All of that was really just a long way of saying the 49ers win-loss record looks a ton better than their peripheral statistics, and teams that fit that profile generally regress to their true rating the following year. Now the 49ers made a number of impressive moves this off-season, and that should help them improve -- but it doesn't change the base. The 49ers should improve off a terrible team that ranked 31st in the SRS rating, not improve off a team that went 7-9 last year.

Why am I writing about this now? Because the 49ers are 2-0 in 2007, but it looks more like games 17 and 18 of the 2006 season. Nothing's changed in San Francisco, where they've won both games by a combined four points against two mediocre teams. The 49ers have been out-gained by 259 yards. And they were oh so close to going 0-2, and not 2-0. If Terrence Holt knocks a loose ball out of the end zone in the final minute instead of trying to pick it up, the 49ers lose to the Cards. Only a little more "luck" was necessary to beat the Rams, as a Dante Hall muffed punt late in the game led to the winning score. Note: According to Jeff Sagarin, the Rams are the worst team in the NFL, the 49ers have played the 32nd hardest schedule in the NFL (read: easiest) and rank as the 29th best team.

Certainly it looks like the 49ers are on their way to another season of laughing in the SRS's face. So the question of the day: Do you believe in the 49ers? Do you believe in the SRS? How many more close wins and blowout losses would we need to see out of the 49ers before we can say it's not a fluke? And do they get blown out in Pittsburgh this weekend?

This entry was posted on Friday, September 21st, 2007 at 9:38 am and is filed under General.
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Clearly the underlying statistics are a stronger indicator of future record than current record is (though, of course, SRS might not capture all of them). It's like that in most (all?) sports.

Say the 9ers are a "true" 4-12 team. They've won 2 squeakers already. Since a 16 game season is too short for luck to really even out, it looks like they're a 6-10 team just because of those two close wins. One more and 7-9 isn't out of range, playing the SRS for chumps again.

Doesn't mean anything, just the luck of the oblong bounce. By the way - though I live in Pittsburgh I try to avoid it biasing me - I think the 8½ point spread is way too small. Take the Bumblebees (last week's uniform), lay the points.

I did a similar analysis a while back that calculated expected wins based on team efficiency stats (run/pass/fum/int/pen) rather than point differential.

For 2006, the Niners were expected to win 6.5 games based on their internal efficiencies. This does not take opponenet strength into account however.

So fundamentally, they played well enough to win 7, but didn't get the points against the tougher teams I suppose.

Interestingly, their stats for the 2005 season (Alex Smith's rookie year) were so bad they would have been expected to win about 0.5 games, but won 4. That was the largest (and luckiest) discrepancy of any team in the 5 years I looked at.

Such analysis always makes me wonder about the impact of coaching. Are the 49ers well-coached but lacking in talent, meaning they're bound to get blown out by superior opponents but can play it close and win against other mediocre teams? I'm not sure if that's the impact of quality coaching, but it's possible.

I tend toward your analysis that the 49ers are a mediocre or worse team, but that's based on Alex Smith being a mediocre or worse quarterback. If he improves throughout the season, that could change the 49ers' status.

One further question worth asking: is the 49ers' schedule this season any more difficult than it was last season? If not, then it's possible they can get to 9 wins playing the same way they have (if the luck breaks, of course), without really being that good a team.

The '91 49ers were the 31st largest "underachiever"; they should have won about 12.9 games, but instead won "only" ten. The biggest underachiever ever was the '81 Patriots, who went 2-14 but should have won 6.34 games. The biggest overachiever was the '70 Colts, followed closely by a couple of famous teams -- the '99 Titans and the '98 Cards.

And Dolfan, I'm familiar with Bill Parcells' quote. It just depends on what "you are" means. I don't think there's any ambiguity in the results, it only lies in your definition. As a practical matter, of course you are what you record says -- you can only make the playoffs based on your record. For predictive purposes, it's crystal clear that your record is not the only (or even the main) thing to use.

PV, I'm not sure if the difference can be attributed to coaching. I think it's possible that it can be, but I'm not certain. I do think lots of the outputs of good coaching are already embedded in a team's SRS rating.

You can even forget Dante Hall's muff. Wilkins came up just short on the winning 56 yd FG.

Two games into 07 and they're already the biggest overachievers in the league so far. Yes they should be blown out in Pittsburgh. Steelers have been a much better team, they're at home, and it's AFC vs. NFC.

I think some of the difference can be attributed to coaching. My theory is that performance stats and SRS capture a lot of coaching input, but don't capture in-game tactics very well.

In-game coaching tactics usually only come into play on very critical, very high-leverage situations. By high-leverage I mean situations where a single play can cause a huge swing in the prospects of winning--things like going for it of 4th down, challenging a call, on-side kicks when unexpected--stuff like that.

Single plays won't make a very large impact on the score or on stats. They may only yield 3 points or a 2-yd gain on 4th and 1. But those kinds of coaching decisions can swing the game. The result would be found in the residuals between expectation models (like Pythagorean or SRS) and actual win totals.

But a lot of the difference is just luck too. A coach would need a long career and a fairly consistent record of over/under performance to really draw any conclusions about him.

Agreed, Brian. Another problem is often the right decision may be better 55% of the time, so we're really going to be dealing with small sample sizes. One way to test our "theory" here is to see if coaches' residuals are consistent from year to year. Consider that on my to do list.

I'm not sure the Niners' field position is entirely a matter of luck. Generally, their kick coverage has been very good, and a few times in both games, they'd punt, then the opposing team went 3 and out, then punted back for a gain in field position for the Niners.

Also, they seem to play far better on offense either late in the game or when they are behind, I'm not sure which. I think maybe the play-calling is too conservative earlier in the games, and it's causing the offense to stall.

But even if coaches' residuals were persistent from year to year, that might, in cases like that of the 49ers, simply be because they played in a consistently terrible division. Obviously a team with a consistently weak schedule is going to consistently have a better record than its SRS score will suggest it should (though not, admittedly, by the sort of margin the 06 49ers did).

Pretty much what I expected. Frank Gore shut down, big running day for the Steelers. Though I must say the 49ers had a good pass rush, but Ben still made some plays downfield to Miller and Holmes. They shut down Hines Ward.

3 straight wins by 21+ pts. I know Cowher's started 3-0 one time, but I can't even remember a 3 game stretch where the Steelers won so convincingly. People say it's the opponents (and I agree with that to an extent), but the same thing can be applied to the Pats, who have played 3 losing teams with horrible secondaries.

Actually, I think there are a lot of weak teams in the league so far period. Chargers don't belong in the elite class at this point.

This blowout was a bit of a mirage though. The 49ers are an average team this year, but it's not like the steelers marched all over them, they had a KO return for a TD, a Defensive TD, and a garbage rushing TD.

I'd say the Steelers are a top 6 team, and the 49ers are a top 16 team.

Their SRS will be poor this year because of their coach, in fact it would be interesting to see which coaches are associated to poor SRS in comparison to their record by their lack of interest in trying to win games, and more interest in trying not to lose them. IE, when you're better you still only win by 3.

The derivation of SRS score takes SOS into account quite satisfactorily: that is one of the things that makes SRS score a pretty good measure of true team strength.

But the formula for projecting a team's winning percentage based on its SRS score does not take strength of schedule into accout. That's the point: it's trying to tell us how many games a team should have won, and thus give us a better idea of how many it will win. And because strength of schedule generally regresses to the mean, that's generally a good thing. But when unusual circumstances (like the persistent and all-pervasive suckiness of the NFC West) conspire to grant a team cupcake schedules year after year, a team should be expected to consistently outperform its SRS projected win total, and not because the coach is good.